As shown in FIGS. 1 and 2, a conventional elastic seat of the bicycle brake device is composed of a shaft sleeve 10, a bushing 11, a torsion spring 12, and a fastening bolt 13. The shaft sleeve 10 is rotatably fastened to a brake seat 141 which is in turn fastened to a fork 14. The shaft sleeve 10 is received in a hole of a brake arm 15 as well as an axial hole 111 of the bushing 11 having a locating hole 112. The torsion spring 12 has one end which is received in the locating hole 112 of the bushing 11. The torsion spring 12 further has another end which is received in a locating hole 142 of the fork 14. The elastic seat is then fastened by means of the fastening bolt 13.
The prior art elastic seat of the bicycle brake device described above has inherent shortcomings, which are expounded explicitly hereinafter.
The prior art elastic seat of the bicycle brake device is made up of component parts which can not be assembled easily.
The torsion spring 12 of the prior art elastic seat of the bicycle brake device is rather vulnerable to a mechanical fatigue in view of the fact that the torsion spring 12 is not protected by a shield.
The prior art elastic seat of the bicycle brake device is not fastened securely with the brake seat 141 in view of the fact that the shaft sleeve 10 is not fully mounted on the brake seat 141, and that the brake seat 141 is susceptible to breakage caused by the action force exerting on the brake seat 141.